A comparison of sonographic cervical parameters in predicting spontaneous preterm birth in high-risk singleton gestations

Authors

  • Dr E. R. Guzman,

    Corresponding author
    1. Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal—Fetal Medicine and Section of Epidemiology and Biostatistics, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Saint Peter's University Hospital, New Brunswick, New Jersey, USA
    • Saint Peter's University Hospital, 254 Easton Avenue, MOB 4th Floor, New Brunswick, New Jersey, USA
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  • C. Walters,

    1. Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal—Fetal Medicine and Section of Epidemiology and Biostatistics, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Saint Peter's University Hospital, New Brunswick, New Jersey, USA
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  • C. V. Ananth,

    1. Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal—Fetal Medicine and Section of Epidemiology and Biostatistics, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Saint Peter's University Hospital, New Brunswick, New Jersey, USA
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  • C. O'Reilly-Green,

    1. Department of Obstetrics, Gynecology and Women's Health, Lennox Hill Hospital, New York, USA
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  • C. W. Benito,

    1. Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal—Fetal Medicine and Section of Epidemiology and Biostatistics, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Saint Peter's University Hospital, New Brunswick, New Jersey, USA
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  • A. Palermo,

    1. Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal—Fetal Medicine and Section of Epidemiology and Biostatistics, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Saint Peter's University Hospital, New Brunswick, New Jersey, USA
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  • A. M. Vintzileos

    1. Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal—Fetal Medicine and Section of Epidemiology and Biostatistics, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Saint Peter's University Hospital, New Brunswick, New Jersey, USA
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Abstract

Objectives

To assess the role of cervical sonography and to compare various sonographic cervical parameters in their ability to predict spontaneous preterm birth in high-risk singleton gestations.

Design

A prospective cohort of 469 high-risk gestations were longitudinally evaluated between 15 and 24 weeks' gestation on 1265 occasions with transvaginal cervical sonography and transfundal pressure. The cervical parameters obtained were funnel width and length, cervical length, percent funneling and cervical index. The information obtained was used for patient management. Restriction of physical activities was initiated at cervical lengths of ≤ 2.5 cm with cerclage as an option for cervical lengths of ≤ 2.0 cm.

Results

Receiver operating characteristic curve analyses showed that a cervical length of ≤ 2.5 cm between 15 and 24 weeks' gestation was equal to the other sonographic cervical parameters in its ability to predict spontaneous preterm birth. The sensitivities for delivery at < 28, < 30, < 32 and < 34 weeks' gestation were 94%, 91%, 83% and 76%, respectively, while the negative predictive values were 99%, 99%, 98% and 96%, respectively. The placement of a cerclage did not influence the positive and negative predictive values. In comparison to women with other risk factors, cervical length was best in the prediction of preterm birth in women with a prior mid-trimester loss; an optimal cut-off of ≤ 1.5 cm had sensitivities for delivery at < 28, < 30, < 32 and < 34 weeks' gestation of 100%, 100% 92% and 81%, respectively. The rate of preterm delivery at < 34 weeks' gestation increased dramatically when the cervical length was ≤ 1.5 cm. Cervical length was the only independent variable that entered the logistic regression model for the prediction of preterm delivery at < 34 weeks' gestation.

Conclusions

In high-risk singleton gestations a cervical length of ≤ 2.5 cm was equal to other sonographic cervical parameters in its ability to predict spontaneous preterm birth and was better for the prediction of earlier forms of prematurity (at < 28 and < 30 weeks) than later forms (at < 32 and < 34 weeks). The optimal cervical lengths and their performance for predicting prematurity may be influenced by obstetric risk factors. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology

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